[clang] [clang-tools-extra] [Clang] Make the SizeType, SignedSizeType and PtrdiffType be named sugar types instead of built-in types (PR #143653)

[Matheus Izvekov via cfe-commits]

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@@ -2767,6 +2767,10 @@ class DependentBitIntTypeLoc final
     : public InheritingConcreteTypeLoc<TypeSpecTypeLoc, DependentBitIntTypeLoc,
                                        DependentBitIntType> {};
 
+class PredefinedSugarTypeLoc final
+    : public InheritingConcreteTypeLoc<TypeSpecTypeLoc, PredefinedSugarTypeLoc,
+                                       PredefinedSugarType> {};
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mizvekov wrote:

These should ideally never be used in practice, as a PredefinedUserType is never written in source code.
I wonder how hard it is to avoid it. Where is this coming up?

https://github.com/llvm/llvm-project/pull/143653